Detection of novel genetic markers by mismatch analysis.

Chemical mismatch detection has been used to identify previously unknown genomic sequence variations that represent a new source of markers for genetic analysis. The approach detects all types of sequence changes, and therefore overcomes the limitation of restriction analysis, which identifies only a small fraction of the available sequence variations. Three new markers identified at the 3' end of the human dystrophin gene result from variable numbers of exact tandem repeats of 4bp (two examples) or 5bp (one example). None of these would have been detected as restriction fragment length polymorphisms by established procedures.